1. Field of the Invention
The present invention relates to a method and apparatus for stereoscopic viewing of a patient's body cavity and particularly such a method incorporating conventional endoscopes.
2. Description of the Prior Art
Endoscopes have commonly been utilized in surgery to enable the surgeon to view the body cavity through relatively small incisions thereby minimizing trauma and post operative pain and recovery.
Conventional endoscopes typically provide for viewing the internal organs in the form of a planar object without a three dimensional view thus limiting the effectiveness, efficiency and convenience for the surgeon in achieving the objective of the operation. The advantages attendant stereoscopic viewing of a patient's internal organs through a small incision have long been known. The recognition of these advantages have led to the development of various sophisticated methods and equipment in effort to devise an endoscopic probe for insertion through a small incision into a body cavity to enable the surgeon to view the surgery by three dimensional television. However, the devices proposed for such endoscopic systems are typically technically sophisticated requiring significant development costs and capital investment beyond the financial capability of many of the present day medical institutions. Thus, surgeons on the staff of the majority of such institutions are currently left without the capability of performing endoscopic surgery with the benefit of stereoscopic observation of the surgery site.
Substantial work has been performed in the field. It has been proposed to provide a binocular endoscope housed in a tube combined with a conduit for irrigation and including a gear mechanism for rotating an optical shaft within the tube. A device of this type is shown in U.S. Pat. No. 4,061,135 to Widran. The system disclosed is rather sophisticated, expensive and fails to incorporate video cameras and monitors enabling effective use of existing non-stereoscopic endoscopes in any combination which will achieve a perspective view of the surgical site.
It has been proposed to provide a custom made stereoscopic endoscope housed in a sheath bundling a pair of image guides, a light guide and various other channels for air, water, gas or other liquids. A device of this type is shown in U.S. Pat. No. 4,651,201 to Schoolman. While recognizing the advantages of stereoscopic endoscopes, the devices described is relatively complicated, cumbersome, expensive to manufacture and inconvenient to use.
It has also been proposed to provide a arthroscope for viewing of human or animal joints which includes a prism arrangement in effort to achieve stereoscopic capability. A device of this type is shown in U.S. Pat. No. 4,924,853 to Jones. A device of this type requires relatively sophisticated technology and is expensive to manufacture.
Other efforts to provide a stereoscope endoscope device includes the proposal of a pair of flexible endoscopes incorporated in a pair of fiber optical systems to be viewed through oculars. A device of this type is shown in U.S. Pat. No. 3,520,587 to Tasaki. While providing certain benefits, such a device suffers the shortcoming that it is expensive to manufacture and compromises the advantages of rigidity in endoscopes for manipulation in a body cavity.
Other efforts to achieve stereoscopic viewing of internal organs includes the provision of a sophisticated flashing strobe lamp with a synchronized rotating prism as shown in U.S. Pat. No. 4,862,873 to Yajima and an electronic endoscopic device as shown in U.S. Pat. No. 4,926,257 to Miyazaki.
The general thinking of current day manufacturers of stereoscopic thoracoscopes aims at miniaturization for introduction of a probe through a single small incision. Manufacturers such as Zeiss and Baxter have proposed such thoracoscopic systems and they estimate that, when FDA approval is achieved, each such system may well require a capital investment of $40,000.00 to $50,000.00. Thus, there exists a need for a practical and inexpensive stereoscopic endoscopic apparatus which will make the benefits of stereoscopic viewing available to a wider range of medical institutions and to surgeons practicing in less affluent geographic areas.
Such a method and apparatus should provide adequate three dimensional visualization for video assisted surgery. An additional benefit would be the capability of adding stereoscopic endoscopy to a single thoracoscope during surgery in the event difficulty is encountered in making the dissection or other surgical procedure.